Copy URL+ add-on for Firefox on Ubuntu

This blog entry describes how to make the CopyURL+ add-on work
with more recent versions of Firefox running on Ubuntu.

Download the cross-platform install (XPI) file of version
1.3.2 of Copy URL+:

wget http://downloads.mozdev.org/copyurlplus/copyurlplus-v1.3.2.xpi

Since the XPI (pronounced "zippy") is just a ZIP file, use
unzip to extract the install.rdf from the
downloaded file:

unzip copyurlplus-v1.3.2.xpi install.rdf

Next, use your favourite editor to change the 1.6 at line 23
of install.rdf - in my case - by 3.5, for
example. Make it at least as high as the current Firefox
version you're using. Before:

<em:maxVersion>1.6</em:maxVersion>

and after:

<em:maxVersion>3.5</em:maxVersion>

Note: if you're unsure of the right
location either change all <em:maxVersion>
values to the same higher value, or make sure that the value
you changes follows the <em:id> with the
following value:
{ec8030f7-c20a-464f-9b0e-13a3a9e97384}

Save the modified file, and add it back to the XPI file as follows:

zip -f copyurlplus-v1.3.2.xpi install.rdf

The -f option to zip, freshen, adds the updated
install.rdf to
copyurlplus-v1.3.2.xpi. If the file was changed
by you, you will see a message similar to the one below:

freshening: install.rdf (deflated 61%)

Next, drag and drop the XPI file onto the main window of
Firefox. A dialog titled "Software Installation" should
open. Click the "Install Now" button. A new dialog window,
named "Add-ons" should pop up, showing "Copy URL + 1.3.2",
followed by the message: "Restart to complete the
installation". Click the "Restart Firefox" button.

After Firefox has restarted, the "Add-ons" dialog window
should show up again with the following message near the top:

1 new add-on has been installed

You should also see the Copy URL + extension in the list of
add-ons. Just close this window.

Now is also a good time to clean up the downloaded file, and
the modified file:

rm -i install.rdf install.rdf~ copyurlplus-v1.3.2.xpi

Note that I've used the -i (interactive) option with
rm allowing me to think again if I really want
to delete each file. The file that has its name end in a
tilde (~) is a back up made by the editor, gedit, I used to
modify the install.rdf file. Since I don't need it anymore,
I delete it as well.

Finally, if you want to use the same or similar
customization as I use (see: Copy URL+ extension for Firefox), first find out the
directory Firefox has assigned to your profile:

ls -al ~/.mozilla/firefox

If you have only one profile in use, you should see output
similar to:

Next, use an editor to extend the user.js
file. I used the following command to start the gedit editor
and open the aforementioned file:

gedit ~/.mozilla/firefox/528s8w95.default/user.js

Now visit Copy URL+ extension for Firefox and
copy the user.js lines given on that page. Next time you
start Firefox, the Copy URL+ menu should have 14 entries:
the default one, and the 13 defined in user.js.